Warning over rise in UK's most dangerous spider due to warmer winters

It may be no bigger than a pea, but its bite can put grown men in hospital.

And thanks to global warming, the false black widow spider is on the march across the country, posing a threat to gardeners and anyone else spending time outdoors.

Officially called steatoda nobilis, it is closely related to the black widow spider whose poison can be fatal to humans.

The species had kept a low profile since arriving in Britain with a cargo of bananas from the Canary Islands 200 years ago.

But according to Stuart Hine, an insect expert at the Natural History Museum, it is rapidly spreading.

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Global warming has led to the rapid rise in numbers of the false widow spider in Britain

"There is no doubt in my mind that this is due to the milder winters caused by global warming," he said.

"Every year, the UK is breaking records for warm temperatures and it is these temperatures that are keeping the spiders alive.

"It used to be only a handful of spiders would be able to survive the cold weather so the numbers were always kept down. But now they are all surviving the winter and are crawling out of hibernation earlier to mate.

"The numbers have just rocketed into the hundreds of thousands.

"They can hide in gardening gloves and will bite when you put your hand in. We would urge gardeners to be on their guard in the future."

A bite from the false black widow delivers enough poison to cause severe pain and inflammation.

Last year market trader Jason Fricker, 34, from Dorchester, Dorset, spent three days in hospital after one bit him on the chest.

An entry on the Natural History Museum's website said a bite from the spider at first caused a burning sensation.

It then "increased in intensity, like being scalded, stabbing pains spread first to armpit then down right arm".

The entry concluded: "Also flu-like symptoms, aches, sweats, fatigue, perspiring, cold and shaky. Face and right arm went purplish and slightly puffy. Felt unwell for three days." Another victim reported that the bite lasted for a similar time before becoming infected.

One study found that the pain was far more severe than that from a wasp or bee sting.

Mr Hine added: "Normally an antihistamine cream will take the pain away but, depending on the amount of venom injected, a doctor may need to be seen."

The species - only the female of which bites - had been considered native to Dorset but has spread as far as East Anglia. It usually lives on walls, fences and tree bark.

Two of the spiders were found by Michael and Pam Willis in their garden in Verwood, Dorset.

Mrs Willis, 62, said: "I saw this elegant black spider crawling down the wall and then it scuttled into the electricity box. It looked totally different, not like your normal hairy spider - it was ever so shiny.

"I am petrified of spiders but managed to catch one of them in a jar as I could tell it was unusual.

"We took it to environmental health experts and they confirmed it was a false widow."